float angulo = 0;

void setup() {
  smooth();
  size(600, 600);
  frameRate(30);
  noStroke();
  background(128);
} 

void draw() {
  fill(255);
  ellipse(300,300,600,600);
  fill(0);
  arc(300,300,600,600,PI-angulo,2*PI-angulo);
  fill(255);
  float x = sin(angulo+PI/2)*150;
  float y = cos(angulo+PI/2)*150;
  ellipse(300+x,300+y,300,300);
  fill(0);
  ellipse(300-x,300-y,300,300);
  fill(255);
  ellipse(300-x,300-y,60,60);
  fill(0);
  ellipse(300+x,300+y,60,60);
  angulo = angulo + PI/30;
}



